HOMOPTEEA. 311 



bulk, that it is not nnfrequently used in commerce in 

 the place of money, changing hands several times, and 

 making many journeys before arriving at its final desti- 

 nation. 



Within a few years of the present time the brightest 

 and only fast red dye was obtained from this insect, 

 which was famous even in the times of the Greeks and 

 Eomans. Many species, from many countries, and dif- 

 fering greatly in value, have been used in dyeing, the 

 most valuable of all being a Mexican species living on 

 one of the Cacti, and which may be met with in English 

 hothouses.* 



The Lac (called shell-lac, stick-lac, &c., according to 

 the manner of its preparation), which is used in the 

 making of sealing-wax, different varnishes, as Japan, 

 the lacquer used on metal, and of the pigments known 

 by the name of "Lake," is produced by an Indian 

 species of the Cochineal family, and is another valuable 

 article of commerce. 



The Cochineal insect is used also in medicine, both as 

 a remedy and for the purpose of colouring other pre- 

 parations. 



The little seed-like, narrow brown scales, so common 

 on the rind of oranges, are the remains of a species of 

 Coccus. 



* The insects are exported in various states, the best and commonest 

 being that called "in grain" i.e., the insects whole, and with somewhat 

 of the appearance of small grains. Thus, "scarlet grain of Poland;" in 

 Spain "grana," or when broken "granilla." From this, the "scarlet in 

 grain," (formerly, as has been said, the only fast bright-red dye) probably 

 arose by degrees the application of the title " ingrain" or "ingrained" to 

 other bright colours as the means of making them fast were discovered. 

 A few years ago the only colours called " ingrain" were this fast red and a 

 then new fast bright blue. 



